Cooling cowl for jet engines



Sept 13, 1955 A. HAsBRoUcK COOLING cowL EOE JET ENGINES 2 Sheets-Sheet lF' led DGO. l1 195] INVENTOR.

Sept. 13, 1955 A. HAsBRoUcK COOLING COWL. FOR JET ENGINES 2 Sheets-SheetUnited States Patent Oce I 2,717,489 latented Sept. 13, 1955 COOLINGCOWL FR JET ENGINES Augustus Hasbrouck, Middletown, Conn.

Application December 11, 1951, Serial No. 261,001

6 Claims. (Cl. 60-35.6)

The invention described herein may be manufactured and used by or forthe Government for governmental purposes without payment to me of anyroyalty thereon.

This invention relates to a system for cooling the components of a jetengine. Since the components of the engine are in a large part subjectto radiant heating from theengine, it is an object of this invention tocool the engine components so that they may perform accurately andadequately.

Another object of this invention is to provide a cooling system whichwill not greatly increase the drag on the airplane.

Another object of this invention is to remove the high ambienttemperature air from the engine components located below the jet engine.

A further object of this invention is to prevent the high temperatureissuing from the jet engine from radiating through the jet engine casingand heating the air surrounding the engine components to a hightemperature.

The average temperature of the engine case immediately above the enginecomponents and at 100% engine speed is 700 F. ln order for the enginecomponents to operate accurately it has been found necessary to hold theambient temperature at 160 F., therefore, a still further object of thisinvention is to provide a cooling system which will maintain 160 F.temperature around the engine components.

The objects of the invention may be realized by the following detailedspecification and accompanying drawings. In the drawings, similar partshave like numbers wherein:

Figure 1 is a side view partially in cross-section showing the lowerpart of the jet engine, a cowling surrounding the engine componentslocated below the engine, and the flow of air through the cowling.

Figure 2 is a partial cross-sectional view taken on line f 2-2 of Figurel showing one of the inlet ports and the contour of the cowling.

Referring to Figures l and 2, the cowling 10 encloses engine components12, shown in phantom lines, which comprise the fuel pump, fuel control,fuel ilowmeter, pressurizing valve, dump valve, and ignition systemlocated below the jet engine 9. The cowling 10 comprises a permanentupper shield 11, connected to but spaced from the engine 9, a removableaccess panel 15, which is preferably of one piece as shown but which maybe made of two halves, and an underside door 17 with the ignition systemmounted thereon, said door 17 being hingedly connected to the forwardportion 19 of the cowling 10 so that upon opening of the door 17 orremoval of said panel easy access to the components for repairing orreplacement is provided. Shield 11 contains air inlets 14 located oneach side of the cowling for the passage of air into the cowling, andair outlets 16 for the exit of lair therefrom. The top portion 18 ofshield 11 is formed to surround the under portion of the engine 9 andspaced therefrom by being concaved. The shield 11 is attached to theengine by brackets 20 and 22. A panel 24 is spaced from the top portion18 and is coextensive therewith and connected thereto such as bywelding. The panel 24 is supplied with an opening 26 toward the rear ofsaid panel for the passage of air therethrough. The panel 24 and upperportion 18 form a shallow passageway 28 which acts as a heat exchangersince the air flow through the air passageway continually removes alarge portion of the high temperature air before it gets an opportunityto radiate through the panel 24 to the engine components 12. Some heatradiating through the panel 24 will be picked up by the air ow from theinlet port 14 beneath the panel 24 and carried through the heatexchanger to the outlet 16. A spun glass insulating blanket 30 isprovided in the space 29 between the engine 9 and the top portion 18 ofthe shield 11. This insulating blanket aids in protecting the criticalcomponent units from the radiant heat of the engine.

In operation air enters at inlets 14 passing rearwardly underneath thepanel 24 and over the engine components 12, up through the opening 26 inpanel 24, then forwardly through the heat exchanging shallow passageway28 and then out through openings 16 to the atmosphere.

inaccuracies result when the engine components operate in highertemperatures. Through this arrangement an operating temperature notexceeding F. may be maintained about the engine components at speedsbetween 400 miles pcr hour and 522 miles per hour.

It is apparent, the specific invention shown above has been given by wayof illustration and not by way of limitation and that the structuresabove described are subject to wide variation and modification withoutdeparting from the scope or intent of the invention, all of whichvariations and modifications are to be included within the scope of thepresent invention.

Whereby I claim:

1. A cooling system for cooling the components of an aircraft enginecomprising a cowling provided with inlet air ports at the forward endthereof and outlet air ports at the sides thereof enclosing the enginecomponents, said cowling being spaced from but connected to the engine,adjacent the upper portion of the cowling there is provided a panelhaving an opening at the rear portion thereof, said panel beingcoextensive with, spaced from, and connected to the upper side of thecowling to form a heat exchanging shallow air passageway near the top ofsaid cowling, whereby said entering through the inlet port at theforward end of the cowling passes over the engine components to the rearand then is directed up through the opening in said panel and forwardthrough the air passageway to the air outlets.

2. The combination of claim 1 wherein an insulating blanket is providedin the space between the engine and the cowling for protecting thepassageway from heat from the engine.

3. A cowling enclosing the components of an engine, said cowling beingspaced from and connected to the engine, and extending along theunderside thereof, a spaced panel in said cowling coextensive with andadjacent to the upper portion of the cowling and connected thereto toform a heat exchanging shallow passageway, an inlet port below saidpanel at the forward end of said cowling for the entrance of airrearwardly, an opening at the rear end of said panel for the entrance ofair into said shallow passageway, an outlet port at the side of saidcowling for the exit of air from said cowling.

4. A combination of claim 3 wherein an insulating blanket is provided inthe space between the engine and the cowling for protecting thepassageway from heat from the engine.

5. A cowling enclosing the components of an engine, said cowling havinga top portion adjacent said engine which is concavely curved partiallysurrounding said engine, and a concave panel spaced from said topportion References Cited inthe le of this patent of vsaid Cowling toform a heat exchanging shallow pas- UNITED STATES PATENTS sageway, andopenings in said Cowling and panel for permitting the flow of airtherethrough. 2,43 2,35 9 Streid DeC- 9, 1947 6. A Cowling enclosing thecomponents of 'a jet engine, 5 474,068 Sammons et al June 21 1949 saidcowlrlig comprising an upper concaved slliie'ld having FOREIGN PATENTSdownwar y extending sides and inlet and out et air ports,

a removable access panel interlocking with said shield, 622768 GreatBmam May 6 1949 a door hinged to the underside of said access panel, theopening of 'said door and the removal of said panel peri() mittingaccess to the engine components. l

